1. Field of the Invention
The present invention relates to an imaging apparatus, and specifically, relates to an imaging apparatus including a multifocal lens having a plurality of focal distances.
2. Description of the Related Art
Recent years, imaging apparatuses have been known each of which includes a multifocal lens having a plurality of focal distances. For example, PTL 1 discloses an imaging optical system using a multifocal lens which system secures the depth of focus by setting a focal distance ratio or an incident pupil area ratio between the inner region and the outer region within a predetermined range, this enabling image capturing to be performed simultaneously for object points large in difference between their object point distances without employing any movable part. Moreover, PTL 2 discloses an endoscope optical system using a lens with a plurality of focal points in which system a bright image can be obtained while securing an observation range by changing the shape of opening of the aperture stop.